Paget’s disease(PDB)is a late-onset bone remodeling disorder with a broad spectrum of symptoms and complications.One of the most aggressive forms is caused by the P937R mutation in the ZNF687 gene.Although the geneti...Paget’s disease(PDB)is a late-onset bone remodeling disorder with a broad spectrum of symptoms and complications.One of the most aggressive forms is caused by the P937R mutation in the ZNF687 gene.Although the genetic involvement of ZNF687 in PDB has been extensively studied,the molecular mechanisms underlying this association remain unclear.Here,we describe the first Zfp687 knock-in mouse model and demonstrate that the mutation recapitulates the PDB phenotype,resulting in severely altered bone remodeling.Through microcomputed tomography analysis,we observed that 8-month-old mutant mice showed a mainly osteolytic phase,with a significant decrease in the trabecular bone volume affecting the femurs and the vertebrae.Conversely,osteoblast activity was deregulated,producing disorganized bone.Notably,this phenotype became pervasive in 16-month-old mice,where osteoblast function overtook bone resorption,as highlighted by the presence of woven bone in histological analyses,consistent with the PDB phenotype.Furthermore,we detected osteophytes and intervertebral disc degeneration,outlining for the first time the link between osteoarthritis and PDB in a PDB mouse model.RNA sequencing of wild-type and Zfp687 knockout RAW264.7 cells identified a set of genes involved in osteoclastogenesis potentially regulated by Zfp687,e.g.,Tspan7,Cpe,Vegfc,and Ggt1,confirming its role in this process.Strikingly,in this mouse model,the mutation was also associated with a high penetrance of hepatocellular carcinomas.Thus,this study established an essential role of Zfp687 in the regulation of bone remodeling,offering the potential to therapeutically treat PDB,and underlines the oncogenic potential of ZNF687.展开更多
Anti-reflective (AR) single layer of silica-titania (SiO2-TiO2) coatings were obtained from sols containing pyromellitic dianhydride (PMDA) derivatives and Ti and Si precursors on glass substrate by dip-coating method...Anti-reflective (AR) single layer of silica-titania (SiO2-TiO2) coatings were obtained from sols containing pyromellitic dianhydride (PMDA) derivatives and Ti and Si precursors on glass substrate by dip-coating method. The coatings showed very high optical quality and the transmission was improved to up to 98.5%. Furthermore, the coatings also presented good mechanical stability.展开更多
Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influenc...Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influence of the structural depth of line patterns coated with multi-walled carbon nanotubes(CNTs)and carbon onions(COs)on their respective potential to reduce friction and wear.Direct laser interference patterning(DLIP)with a pulse duration of 12 ps is used to create line patterns with three different structural depths at a periodicity of 3.5μm on AISI 304 steel platelets.Subsequently,electrophoretic deposition(EPD)is applied to form homogeneous carbon nanoparticle coatings on the patterned platelets.Tribological ball-on-disc experiments are conducted on the as-described surfaces with an alumina counter body at a load of 100 mN.The results show that the shallower the coated structure,the lower its coefficient of friction(COF),regardless of the particle type.Thereby,with a minimum of just below 0.20,CNTs reach lower COF values than COs over most of the testing period.The resulting wear tracks are characterized by scanning electron microscopy,transmission electron microscopy,and energy-dispersive X-ray spectroscopy.During friction testing,the CNTs remain in contact,and the immediate proximity,whereas the CO coating is largely removed.Regardless of structural depth,no oxidation occurs on CNT-coated surfaces,whereas minor oxidation is detected on CO-coated wear tracks.展开更多
Adhesion between an elastic body and a smooth,rigid substrate can lead to large tensile stresses between them.However,most macroscopic objects are microscopically rough,which strongly suppresses adhesion.A fierce deba...Adhesion between an elastic body and a smooth,rigid substrate can lead to large tensile stresses between them.However,most macroscopic objects are microscopically rough,which strongly suppresses adhesion.A fierce debate has unfolded recently as to whether local or global parameters determine the crossover between small and large adhesion.Here,we report simulations revealing that the dependence of the pull-off force Fn on the surface energyγdoes not only have two regimes of high and low adhesion but up to four regimes.They are related to contacts,which at the moment of rupture consist of(i)the last individual Hertzian-shaped contact,in which is linear inγ,(ii)a last meso-scale,individual patches with super-linear scaling,(iii)many isolated contact patches with extremely strong scaling,and(iv)a dominating largest contact patch,for which the pull-off stress is no longer negligible compared to the maximum,microscopic pull-off stress.Regime(iii)can be seen as a transition domain.It is located near the point where the surface energy is half the elastic energy per unit area in conformal contact.A criterion for the transition between regimes(i)and(ii)appears difficult to grasp.展开更多
Heavy metal pollution is a key environmental problem.Selectively extracting heavy metals could accomplish water purification and resource recycling simultaneously.Adsorption is a promising approach with a facile proce...Heavy metal pollution is a key environmental problem.Selectively extracting heavy metals could accomplish water purification and resource recycling simultaneously.Adsorption is a promising approach with a facile process,adaptability for the broad concentration of feed water,and high selectivity.However,the adsorption method faces challenges in synthesizing highperformance sorbents and regenerating adsorbents effectively.FeOOH is an environmentally friendly sorbent with low-cost production on a large scale.Nevertheless,the selectivity behavior and regeneration of FeOOH are seldom studied.Therefore,we investigated the selectivity of FeOOH in a mixed solution of Co^(2+),Ni^(2+),and Pb^(2+)and proposed to enhance the capacity of FeOOH and regenerate it by using external charges.Without charge,the FeOOH electrode shows a Pb^(2+)uptake capacity of 20 mg/g.After applying a voltage of-0.2/+0.8 V,the uptake capacity increases to a maximum of 42 mg/g and the desorption ratio is 70%-80%.In 35 cycles,FeOOH shows a superior selectivity towards Pb^(2+)compared with Co^(2+)and Ni^(2+),with a purity of 97%±3%in the extracts.The high selectivity is attributed to the lower activation energy for Pb^(2+)sorption.The capacity retentions at the 5^(th)and the 35^(th)cycles are ca.80%and ca.50%,respectively,comparable to the chemical regeneration method.With industrially exhausted granular ferric hydroxide as the electrode material,the system exhibits a Pb^(2+)uptake capacity of 37.4 mg/g with high selectivity.Our work demonstrates the feasibility of regenerating FeOOH by charge and provides a new approach for recycling and upcycling FeOOH sorbent.展开更多
Neuroimaging techniques such as magnetic resonance imaging(MRI)and positron emission tomography provide unique in vivo data to analyze structural and functional connectivity of the whole brain.Recent advances in small...Neuroimaging techniques such as magnetic resonance imaging(MRI)and positron emission tomography provide unique in vivo data to analyze structural and functional connectivity of the whole brain.Recent advances in small animal neuroimaging have opened new opportunities for the study of structure-function interactions in healthy and diseased brain networks,which are essential to develop therapies targeting network reorganization associated with functional improvement.展开更多
In recent years,forest fires and maritime accidents have occurred frequently,which have had a bad impact on human production and life.Thus,the development of seaplanes is an increasingly urgent demand.It is important ...In recent years,forest fires and maritime accidents have occurred frequently,which have had a bad impact on human production and life.Thus,the development of seaplanes is an increasingly urgent demand.It is important to study the taxiing process of seaplanes for the development of seaplanes,which is a strong nonlinear fluid-structure interaction problem.In this paper,the smoothed particle hydrodynamics(SPH)method based on the Lagrangian framework is utilized to simulate the taxiing process of seaplanes,and the SPH results are compared with those of the finite volume method(FVM)based on the Eulerian method.The results show that the SPH method can not only give the same accuracy as the FVM but also have a strong ability to capture the splashing waves in the taxiing process,which is quite meaningful for the subsequent study of the effect of a splash on other parts of the seaplane.展开更多
Stroke is the second leading cause of death worldwide with about 50% of survivors being chronically disabled(Donkor,2018).The behavioral improvement seen in stroke patients in the first weeks after a stroke is contrib...Stroke is the second leading cause of death worldwide with about 50% of survivors being chronically disabled(Donkor,2018).The behavioral improvement seen in stroke patients in the first weeks after a stroke is contributed by behavioral compensation, reorganization in somatotopic maps and activity in peri-infarct but also distant regions which are connected to the stroke area as supported by animal studies.展开更多
The human striatum is essential for both lowand high-level functions and has been implicated in the pathophysiology of various prevalent disorders,including Parkinson's disease(PD)and schizophrenia(SCZ).It is know...The human striatum is essential for both lowand high-level functions and has been implicated in the pathophysiology of various prevalent disorders,including Parkinson's disease(PD)and schizophrenia(SCZ).It is known to consist of structurally and functionally divergent subdivisions.However,previous parcellations are based on a single neuroimaging modality,leaving the extent of the multi-modal organization of the striatum unknown.Here,we investigated the organization of the striatum across three modalities—resting-state functional connectivity,probabilistic diffusion tractography,and structural covariance—to provide a holistic convergent view of its structure and function.We found convergent clusters in the dorsal,dorsolateral,rostral,ventral,and caudal striatum.Functional characterization revealed the anterior striatum to be mainly associated with cognitive and emotional functions,while the caudal striatum was related to action execution.Interestingly,significant structural atrophy in the rostral and ventral striatum was common to both PD and SCZ,but atrophy in the dorsolateral striatum was specifically attributable to PD.Our study revealed a cross-modal convergent organization of the striatum,representing a fundamental topographical model that can be useful for investigating structural and functional variability in aging and in clinical conditions.展开更多
Dear Editor,Adeno-associated virus(AAV)is one of the most powerful vectors for exogenous gene delivery.1 However,the risks associated with the high dosages of AAV administration that are required to achieve meaningful...Dear Editor,Adeno-associated virus(AAV)is one of the most powerful vectors for exogenous gene delivery.1 However,the risks associated with the high dosages of AAV administration that are required to achieve meaningful effects limit the applicability of this method.Generally,AAV only presents cell autonomous manner in infected cells.Besides,mosaic genetic editing or gene therapy would trigger global biological function restore by above 30–40%infective ratio in heart diseases.展开更多
Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way...Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way.However,Faradaic materials hold the drawbacks of slow desalination rate due to the intrinsic low ion diffusion kinetics and inferior stability arising from the volume expansion during ion intercalation,impeding the engineering application of capacitive deionization.Herein,a pseudocapacitive material with hollow architecture was prepared via template-etching method,namely,cuboid cobalt hydroxide,with fast desalination rate(3.3 mg(NaCl)·g^(-1)(h-Co(OH)2)·min^(-1)at 100 mA·g^(-1))and outstanding stability(90%capacity retention after 100 cycles).The hollow structure enables swift ion transport inside the material and keeps the electrode intact by alleviating the stress induced from volume expansion during the ion capture process,which is corroborated well by in situ electrochemical dilatometry and finite element simulation.Additionally,benefiting from the elimination of unreacted bulk material and vertical cobalt hydroxide nanosheets on the exterior surface,the synthesized material provides a high desalination capacity(117±6 mg(NaCl)·g^(-1)(h-Co(OH)2)at 30 mA·g^(-1)).This work provides a new strategy,constructing microscale hollow faradic configuration,to further boost the desalination performance of Faradaic materials.展开更多
P2-type layered oxides with the general Na-deficient composition Na_(x)TMO_(2)(x<1,TM:transition metal)are a promising class of cathode materials for sodium-ion batteries.The open Na+transport pathways present in t...P2-type layered oxides with the general Na-deficient composition Na_(x)TMO_(2)(x<1,TM:transition metal)are a promising class of cathode materials for sodium-ion batteries.The open Na+transport pathways present in the structure lead to low diffusion barriers and enable high charge/discharge rates.However,a phase transition from P2 to O2 structure occurring above 4.2 V and metal dissolution at low potentials upon discharge results in rapid capacity degradation.In this work,we demonstrate the positive effect of configurational entropy on the stability of the crystal structure during battery operation.Three different compositions of layered P2-type oxides were synthesized by solid-state chemistry,Na_(0.67)(Mn_(0.55)Ni_(0.21)Co_(0.24))O_(2),Na_(0.67)(Mn_(0.45)Ni_(0.18)Co_(0.24)Ti_(0.1)Mg_(0.03))O_(2) and Na_(0.67)(Mn_(0.45)Ni_(0.18)Co_(0.18)Ti_(0.1)Mg_(0.03)Al_(0.04)Fe_(0.02))O_(2) with low,medium and high configurational entropy,respectively.The high-entropy cathode material shows lower structural transformation and Mn dissolution upon cycling in a wide voltage range from 1.5 to 4.6 V.Advanced operando techniques and post-mortem analysis were used to probe the underlying reaction mechanism thoroughly.Overall,the high-entropy strategy is a promising route for improving the electrochemical performance of P2 layered oxide cathodes for advanced sodium-ion battery applications.展开更多
Hypothalamic receptors for neuropeptide Y, melaninconcentrating hormone, melanocortins and orexins/ hypocretins as well as for the downstream signaling corticotrophic factor have been discussed broadly for their influ...Hypothalamic receptors for neuropeptide Y, melaninconcentrating hormone, melanocortins and orexins/ hypocretins as well as for the downstream signaling corticotrophic factor have been discussed broadly for their influence on food intake and reward but also on several psychiatric disorders. For the development of non-peptide ligands for the in vivo detection of alterations in density and affinity of such G-protein coupled (GPCRs) peptide receptors the requirements to affinity and pharmacokinetics have been shifted to thresholds markedly distict from classical GPCRs to dissociation constants ported originally as potential therapeutics in the treatment of obesity among which some are suitable candidates for labeling as PET or SPECT-tracers providing receptor affinities even below 0.1 nM. These could be unique tools not only for better understanding of the mechanism of obesity but also for investigations of extrahypothalamic role of “feeding receptors” at the interface between neuroendocrine and mental diseases.展开更多
Optimization of composition and microstructure is important to enhance performance of solid oxide fuel cells （SOFC） and lithium-ion batteries （LIB）. For this, the porous electrode structures of both SOFC and LIB a...Optimization of composition and microstructure is important to enhance performance of solid oxide fuel cells （SOFC） and lithium-ion batteries （LIB）. For this, the porous electrode structures of both SOFC and LIB are modeled as a binary mixture of electronic and ionic conducting particles to estimate effective transport properties. Particle packings of 10000 spherical, binary sized and randomly positioned particles are created numerically and densified considering the different manufacturing processes in SOFC and LIB： the sintering of SOFC electrodes is approximated geometrically, whereas the calendering process and volume change due to intercalation in LIB are modeled physically by a discrete el- ement approach. A combination of a tracking algorithm and a resistor network approach is developed to predict the con- nectivity and effective conductivity for the various densified structures. For SOFC, a systematic study of the influence of morphology on connectivity and conductivity is performed on a large number of assemblies with different compositions and particle size ratios between 1 and 10. In comparison to percolation theory, an enlarged percolation area is found, es- pecially for large size ratios. It is shown that in contrast to former studies the percolation threshold correlates to varying coordination numbers. The effective conductivity shows not only an increase with volume fraction as expected but also with size ratio. For LIB, a general increase of conductivity during the intercalation process was observed in correlation with increasing contact forces. The positive influence of cal- endering on the percolation threshold and the effective conductivity of carbon black is shown. The anisotropy caused by the calendering process does not influence the carbon black phase.展开更多
The"solid-liquid"behavior of vitrimers have not been systematically investigated.Herein,a series of"solid-liquid"vitrimers bearing varying contents of dynamic boronic ester bonds were synthesized v...The"solid-liquid"behavior of vitrimers have not been systematically investigated.Herein,a series of"solid-liquid"vitrimers bearing varying contents of dynamic boronic ester bonds were synthesized via thiol-ene click reactions.These vitrimers allow for flexibile modulation of their network structures and thus show a range of intriguing properties including high stretchability,flexible transition from elasticity to plasticity,strong strain rate dependence,and solid-liquid performance.The dynamic association rate of boronic ester bonds within these vitrimers could be apparently accelerated via increasing the content of boronic ester,which could be used to shape-program the flat vitrimer films into various complex 3D structures just with external force.Materials with such versatile dynamic behavior may open up a range of new applications.展开更多
Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) have been known for decades to mediate neuroendocrine and vasodilative actions via G-protein-coupled receptors of Clas...Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) have been known for decades to mediate neuroendocrine and vasodilative actions via G-protein-coupled receptors of Class B. These are targets of imaging probes for positron emission tomography (PET) or single photon emission tomography (SPECT) in tumor diagnostics and tumor grading. However, they play only a subordinate role in the development of tracers for brain imaging. Difficulties in development of non-peptide ligands typical for cerebral receptors of PACAP and VIP are shared by all members of Class B receptor family. Essential landmarks have been confirmed for understanding of structural details of Class B receptor molecular signalling during the last five years. High relevance in the explanation of problems in ligand development for these receptors is admitted to the large N-terminal?ectodomain markedly different from Class A receptor binding sites and poorly suitable as orthosteric binding sites for the most small-molecule compounds. The present study is focused on the recently available receptor ligands for PAC1, VPAC1 and VPAC2 receptors as well as potential small-molecule lead structures suitable for use in PET or SPECT. Recently, biaryl, cyanothiophene and pentanamide structures with affinities in nM-range have been proposed as non-peptide ligands at VPAC1 and VPAC2 receptors. However, most of these ligands have been classified as non-competitive related to the orthosteric binding site of endogenous peptide ligands of VPAC receptors. For PAC1 receptors have been identified hydrazide compounds for which an inhibitory and potentially competitive mechanism of receptor binding has been postulated based on molecular docking studies.展开更多
Neuropeptide receptors of the brain and spinal cord are parts of the pain circuits targeted by analgesic drugs. Some of these receptors have been found in the central nervous system as well as in intracranial vascular...Neuropeptide receptors of the brain and spinal cord are parts of the pain circuits targeted by analgesic drugs. Some of these receptors have been found in the central nervous system as well as in intracranial vascular structures and achieved revival of attention because of their role in acute and chronic pain syndromes. A number of them are of high clinical relevance for e.g. migraine. Others participate in symptoms of rare diseases like amyotrophic lateral sclerosis. Here we will focus on five of the neuropeptide receptors and their non-peptide ligands potentially or already successfully used as PET probes. Opioid receptors and neurotensin receptors are known to mediate analgesic actions. Bradykinin and calcitonin gene-related peptide (CGRP) receptors are known to be involved in the regulation of vascular tone and inflammatory responses, and neurokinin receptors play a role in the occurrence of pain perception in a rather indirect manner. Most experiences as PET tracers have been gathered with opioid receptor ligands and neurokinin receptor ligands. The most innovative fields revealed by the studies summarized in this report are the ligands of κ opioid receptors and CGRP receptors for which a first PET tracer was presented recently.展开更多
Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way...Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way.However,Faradaic materials hold the drawbacks of slow desalination rate due to the intrinsic low ion diffusion kinetics and inferior stability arising from the volume expansion during ion intercalation,impeding the engineering application of capacitive deionization.Herein,a pseudocapacitive material with hollow architecture was prepared via template-etching method,namely,cuboid cobalt hydroxide,with fast desalination rate(3.3 mg(NaCl)·g^(-1)(h-Co(OH)_(2))·min^(-1) at 100 mA·g^(-1))and outstanding stability(90%capacity retention after 100 cycles).The hollow structure enables swift ion transport inside the material and keeps the electrode intact by alleviating the stress induced from volume expansion during the ion capture process,which is corroborated well by in situ electrochemical dilatometry and finite element simulation.Additionally,benefiting from the elimination of unreacted bulk material and vertical cobalt hydroxide nanosheets on the exterior surface,the synthesized material provides a high desalination capacity(117±6 mg(NaCl)·g^(-1)(h-Co(OH)_(2))at 30 mA·g^(-1)).This work provides a new strategy,constructing microscale hollow faradic configuration,to further boost the desalination performance of Faradaic materials.展开更多
基金Italian Association for Cancer Research(AIRC)under IG 2020-ID.25110 projectPOR Campania FESR 2014/2020(Project SATIN)+1 种基金Progetto MISE(F/050011/02/X32)–P.I.Fernando Gianfrancescofunding from the European Calcified Tissue Society(ECTS)and the Italian Society for Osteoporosis,Mineral Metabolism and Skeletal Diseases(SIOMMMS)。
文摘Paget’s disease(PDB)is a late-onset bone remodeling disorder with a broad spectrum of symptoms and complications.One of the most aggressive forms is caused by the P937R mutation in the ZNF687 gene.Although the genetic involvement of ZNF687 in PDB has been extensively studied,the molecular mechanisms underlying this association remain unclear.Here,we describe the first Zfp687 knock-in mouse model and demonstrate that the mutation recapitulates the PDB phenotype,resulting in severely altered bone remodeling.Through microcomputed tomography analysis,we observed that 8-month-old mutant mice showed a mainly osteolytic phase,with a significant decrease in the trabecular bone volume affecting the femurs and the vertebrae.Conversely,osteoblast activity was deregulated,producing disorganized bone.Notably,this phenotype became pervasive in 16-month-old mice,where osteoblast function overtook bone resorption,as highlighted by the presence of woven bone in histological analyses,consistent with the PDB phenotype.Furthermore,we detected osteophytes and intervertebral disc degeneration,outlining for the first time the link between osteoarthritis and PDB in a PDB mouse model.RNA sequencing of wild-type and Zfp687 knockout RAW264.7 cells identified a set of genes involved in osteoclastogenesis potentially regulated by Zfp687,e.g.,Tspan7,Cpe,Vegfc,and Ggt1,confirming its role in this process.Strikingly,in this mouse model,the mutation was also associated with a high penetrance of hepatocellular carcinomas.Thus,this study established an essential role of Zfp687 in the regulation of bone remodeling,offering the potential to therapeutically treat PDB,and underlines the oncogenic potential of ZNF687.
基金The authors gratefully acknowledge the financial support of the Brazilian research funding agency CNPq and the Coordination for the Improvement of Higher Education Personnel(CAPES)
文摘Anti-reflective (AR) single layer of silica-titania (SiO2-TiO2) coatings were obtained from sols containing pyromellitic dianhydride (PMDA) derivatives and Ti and Si precursors on glass substrate by dip-coating method. The coatings showed very high optical quality and the transmission was improved to up to 98.5%. Furthermore, the coatings also presented good mechanical stability.
基金supported by the National Natural Science Foundation of China (Grant Nos.12002404 and 52171329)the Key-Area Research and Development Program of Guangdong Province (Grant Nos.2020B1111010002 and 2020B1111010004)+1 种基金the Natural Science Foundation of Guangdong Province of China (Grant No.2022A1515012084)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University.
基金financial support by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)within the project MU 959/47-1Furthermore,the authors gratefully acknowledge funding in the ZuMat projectsupported by the State of Saarland from the European Regional Development Fund(Europäischer Fonds für Regionale Entwicklung,EFRE).P.Grützmacher and C.Gachot would like to thank the Government of Lower Austria(WST3)for financially supporting the endowed professorship tribology at the TU Wien.V.Presser thanks Eduard Arzt(INM)for his continuing support.
文摘Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influence of the structural depth of line patterns coated with multi-walled carbon nanotubes(CNTs)and carbon onions(COs)on their respective potential to reduce friction and wear.Direct laser interference patterning(DLIP)with a pulse duration of 12 ps is used to create line patterns with three different structural depths at a periodicity of 3.5μm on AISI 304 steel platelets.Subsequently,electrophoretic deposition(EPD)is applied to form homogeneous carbon nanoparticle coatings on the patterned platelets.Tribological ball-on-disc experiments are conducted on the as-described surfaces with an alumina counter body at a load of 100 mN.The results show that the shallower the coated structure,the lower its coefficient of friction(COF),regardless of the particle type.Thereby,with a minimum of just below 0.20,CNTs reach lower COF values than COs over most of the testing period.The resulting wear tracks are characterized by scanning electron microscopy,transmission electron microscopy,and energy-dispersive X-ray spectroscopy.During friction testing,the CNTs remain in contact,and the immediate proximity,whereas the CO coating is largely removed.Regardless of structural depth,no oxidation occurs on CNT-coated surfaces,whereas minor oxidation is detected on CO-coated wear tracks.
文摘Adhesion between an elastic body and a smooth,rigid substrate can lead to large tensile stresses between them.However,most macroscopic objects are microscopically rough,which strongly suppresses adhesion.A fierce debate has unfolded recently as to whether local or global parameters determine the crossover between small and large adhesion.Here,we report simulations revealing that the dependence of the pull-off force Fn on the surface energyγdoes not only have two regimes of high and low adhesion but up to four regimes.They are related to contacts,which at the moment of rupture consist of(i)the last individual Hertzian-shaped contact,in which is linear inγ,(ii)a last meso-scale,individual patches with super-linear scaling,(iii)many isolated contact patches with extremely strong scaling,and(iv)a dominating largest contact patch,for which the pull-off stress is no longer negligible compared to the maximum,microscopic pull-off stress.Regime(iii)can be seen as a transition domain.It is located near the point where the surface energy is half the elastic energy per unit area in conformal contact.A criterion for the transition between regimes(i)and(ii)appears difficult to grasp.
基金L.W.acknowledges funding from the Chinese Scholarship Council(CSC,No.201906260277)The work of L.D.was part of theÉcole Européenne d’Ingénieurs en Génie des Matériaux(EEIGM)carried out at Saarland University.Work at the Molecular Foundry was supported by the Office of Science,Office of Basic Energy Sciences,of the U.S.Department of Energy(No.DE-AC02-05CH11231)We acknowledge support for the eLiRec project by the European Union from the European Regional Development Fund(EFRE)and the State of Saarland,Germany.S.J.Z.acknowledges support from Tulane University.
文摘Heavy metal pollution is a key environmental problem.Selectively extracting heavy metals could accomplish water purification and resource recycling simultaneously.Adsorption is a promising approach with a facile process,adaptability for the broad concentration of feed water,and high selectivity.However,the adsorption method faces challenges in synthesizing highperformance sorbents and regenerating adsorbents effectively.FeOOH is an environmentally friendly sorbent with low-cost production on a large scale.Nevertheless,the selectivity behavior and regeneration of FeOOH are seldom studied.Therefore,we investigated the selectivity of FeOOH in a mixed solution of Co^(2+),Ni^(2+),and Pb^(2+)and proposed to enhance the capacity of FeOOH and regenerate it by using external charges.Without charge,the FeOOH electrode shows a Pb^(2+)uptake capacity of 20 mg/g.After applying a voltage of-0.2/+0.8 V,the uptake capacity increases to a maximum of 42 mg/g and the desorption ratio is 70%-80%.In 35 cycles,FeOOH shows a superior selectivity towards Pb^(2+)compared with Co^(2+)and Ni^(2+),with a purity of 97%±3%in the extracts.The high selectivity is attributed to the lower activation energy for Pb^(2+)sorption.The capacity retentions at the 5^(th)and the 35^(th)cycles are ca.80%and ca.50%,respectively,comparable to the chemical regeneration method.With industrially exhausted granular ferric hydroxide as the electrode material,the system exhibits a Pb^(2+)uptake capacity of 37.4 mg/g with high selectivity.Our work demonstrates the feasibility of regenerating FeOOH by charge and provides a new approach for recycling and upcycling FeOOH sorbent.
基金financial support by the Friebe Foundation:project ID T0498/28960/16the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation):project ID 431549029-SFB 1451.
文摘Neuroimaging techniques such as magnetic resonance imaging(MRI)and positron emission tomography provide unique in vivo data to analyze structural and functional connectivity of the whole brain.Recent advances in small animal neuroimaging have opened new opportunities for the study of structure-function interactions in healthy and diseased brain networks,which are essential to develop therapies targeting network reorganization associated with functional improvement.
基金supported by: the National Key Research and Development Program of China (Grant No. 2021YFC2800700)the National Natural Science Foundation of China (Grant Nos. 52171329 and 12002404)+2 种基金the Natural Science Foundation of Guangdong Province of China (Grant No. 2022A1515012084)the Fundamental Research Funds for the Central Universities, Sun Yat-sen University (Grant No. 231gbi023)supported by the GHfund A (Grant No. ghfund202302014084)
文摘In recent years,forest fires and maritime accidents have occurred frequently,which have had a bad impact on human production and life.Thus,the development of seaplanes is an increasingly urgent demand.It is important to study the taxiing process of seaplanes for the development of seaplanes,which is a strong nonlinear fluid-structure interaction problem.In this paper,the smoothed particle hydrodynamics(SPH)method based on the Lagrangian framework is utilized to simulate the taxiing process of seaplanes,and the SPH results are compared with those of the finite volume method(FVM)based on the Eulerian method.The results show that the SPH method can not only give the same accuracy as the FVM but also have a strong ability to capture the splashing waves in the taxiing process,which is quite meaningful for the subsequent study of the effect of a splash on other parts of the seaplane.
文摘Stroke is the second leading cause of death worldwide with about 50% of survivors being chronically disabled(Donkor,2018).The behavioral improvement seen in stroke patients in the first weeks after a stroke is contributed by behavioral compensation, reorganization in somatotopic maps and activity in peri-infarct but also distant regions which are connected to the stroke area as supported by animal studies.
基金This work was supported by the Deutsche Forschungsgemeinschaft(GE 2835/1-1,El 816/4-1)the Helmholtz Portfolio Theme 4 Supercomputing and Modelling for the Human Brain'and the European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No.785907(HBP SGA2)We gratefully acknowledge financial support from the China Scholarship Council(201606750003).
文摘The human striatum is essential for both lowand high-level functions and has been implicated in the pathophysiology of various prevalent disorders,including Parkinson's disease(PD)and schizophrenia(SCZ).It is known to consist of structurally and functionally divergent subdivisions.However,previous parcellations are based on a single neuroimaging modality,leaving the extent of the multi-modal organization of the striatum unknown.Here,we investigated the organization of the striatum across three modalities—resting-state functional connectivity,probabilistic diffusion tractography,and structural covariance—to provide a holistic convergent view of its structure and function.We found convergent clusters in the dorsal,dorsolateral,rostral,ventral,and caudal striatum.Functional characterization revealed the anterior striatum to be mainly associated with cognitive and emotional functions,while the caudal striatum was related to action execution.Interestingly,significant structural atrophy in the rostral and ventral striatum was common to both PD and SCZ,but atrophy in the dorsolateral striatum was specifically attributable to PD.Our study revealed a cross-modal convergent organization of the striatum,representing a fundamental topographical model that can be useful for investigating structural and functional variability in aging and in clinical conditions.
基金This work was supported by the National Natural Science Foundation of China(81741025 and 81700360)Technology Project of Sichuan Province of China(2020YFS0102).
文摘Dear Editor,Adeno-associated virus(AAV)is one of the most powerful vectors for exogenous gene delivery.1 However,the risks associated with the high dosages of AAV administration that are required to achieve meaningful effects limit the applicability of this method.Generally,AAV only presents cell autonomous manner in infected cells.Besides,mosaic genetic editing or gene therapy would trigger global biological function restore by above 30–40%infective ratio in heart diseases.
基金supported by the National Natural Science Foundation of China(52170087,21777118)the China Schol-arship Council(CSC)via award number 201906260277.
文摘Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way.However,Faradaic materials hold the drawbacks of slow desalination rate due to the intrinsic low ion diffusion kinetics and inferior stability arising from the volume expansion during ion intercalation,impeding the engineering application of capacitive deionization.Herein,a pseudocapacitive material with hollow architecture was prepared via template-etching method,namely,cuboid cobalt hydroxide,with fast desalination rate(3.3 mg(NaCl)·g^(-1)(h-Co(OH)2)·min^(-1)at 100 mA·g^(-1))and outstanding stability(90%capacity retention after 100 cycles).The hollow structure enables swift ion transport inside the material and keeps the electrode intact by alleviating the stress induced from volume expansion during the ion capture process,which is corroborated well by in situ electrochemical dilatometry and finite element simulation.Additionally,benefiting from the elimination of unreacted bulk material and vertical cobalt hydroxide nanosheets on the exterior surface,the synthesized material provides a high desalination capacity(117±6 mg(NaCl)·g^(-1)(h-Co(OH)2)at 30 mA·g^(-1)).This work provides a new strategy,constructing microscale hollow faradic configuration,to further boost the desalination performance of Faradaic materials.
基金financial support from the China Scholarship Council(CSC)financial support by Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany’s Excellence Strategy,EXC 2154,project number 390874152+8 种基金financial support from the Federal Ministry of Education and Research(Bundesministerium für Bildung und Forschung,BMBF)under the project‘KaSiLi’(03XP0254D)in the competence cluster‘Excell-BattMat’financial support from the Helmholtz Association(DigiBat project)support by the German Research Foundation(to H H,Grant No.HA 1344/43-1)is gratefully acknowledgedsupport from EnABLES and EPISTORE,projects funded by the European Union’s Horizon 2020 research and innovation program under Grant Agreement No.730957 and 101017709,respectivelyfunding from the Kera-Solar project(Carl Zeiss Foundation)support at beamline P65 of the PETRA Ⅲ synchrotron(Deutsches Elektronen-Synchrotron DESY,Hamburg,Germany)is gratefully acknowledgedEduard Arzt(INM)for his continuing supportAndrea Jung(INM)for her support on ICP-OES measurementsthe support from the Karlsruhe Nano Micro Facility(KNMF,www.knmf.kit.edu),a Helmholtz research infrastructure at Karlsruhe Institute of Technology(KIT,www.kit.du).
文摘P2-type layered oxides with the general Na-deficient composition Na_(x)TMO_(2)(x<1,TM:transition metal)are a promising class of cathode materials for sodium-ion batteries.The open Na+transport pathways present in the structure lead to low diffusion barriers and enable high charge/discharge rates.However,a phase transition from P2 to O2 structure occurring above 4.2 V and metal dissolution at low potentials upon discharge results in rapid capacity degradation.In this work,we demonstrate the positive effect of configurational entropy on the stability of the crystal structure during battery operation.Three different compositions of layered P2-type oxides were synthesized by solid-state chemistry,Na_(0.67)(Mn_(0.55)Ni_(0.21)Co_(0.24))O_(2),Na_(0.67)(Mn_(0.45)Ni_(0.18)Co_(0.24)Ti_(0.1)Mg_(0.03))O_(2) and Na_(0.67)(Mn_(0.45)Ni_(0.18)Co_(0.18)Ti_(0.1)Mg_(0.03)Al_(0.04)Fe_(0.02))O_(2) with low,medium and high configurational entropy,respectively.The high-entropy cathode material shows lower structural transformation and Mn dissolution upon cycling in a wide voltage range from 1.5 to 4.6 V.Advanced operando techniques and post-mortem analysis were used to probe the underlying reaction mechanism thoroughly.Overall,the high-entropy strategy is a promising route for improving the electrochemical performance of P2 layered oxide cathodes for advanced sodium-ion battery applications.
文摘Hypothalamic receptors for neuropeptide Y, melaninconcentrating hormone, melanocortins and orexins/ hypocretins as well as for the downstream signaling corticotrophic factor have been discussed broadly for their influence on food intake and reward but also on several psychiatric disorders. For the development of non-peptide ligands for the in vivo detection of alterations in density and affinity of such G-protein coupled (GPCRs) peptide receptors the requirements to affinity and pharmacokinetics have been shifted to thresholds markedly distict from classical GPCRs to dissociation constants ported originally as potential therapeutics in the treatment of obesity among which some are suitable candidates for labeling as PET or SPECT-tracers providing receptor affinities even below 0.1 nM. These could be unique tools not only for better understanding of the mechanism of obesity but also for investigations of extrahypothalamic role of “feeding receptors” at the interface between neuroendocrine and mental diseases.
基金supported by the Helmholtz Portfolio "elektrochemische Speicher",particularly the work related to lithium-ion batteriespartially supported as part of the HeteroFoam Center,an Energy Frontier Research Center funded by the U.S.Department of Energy,Office of Science, Basic Energy Sciences(DE-SC0001061)+1 种基金support from the Center for Scientific Computing at the CNSI and MRL:an NSF MRSEC(DMR-1121053) and NSF (CNS-0960316)Australian Research Council Grant DE130101639
文摘Optimization of composition and microstructure is important to enhance performance of solid oxide fuel cells （SOFC） and lithium-ion batteries （LIB）. For this, the porous electrode structures of both SOFC and LIB are modeled as a binary mixture of electronic and ionic conducting particles to estimate effective transport properties. Particle packings of 10000 spherical, binary sized and randomly positioned particles are created numerically and densified considering the different manufacturing processes in SOFC and LIB： the sintering of SOFC electrodes is approximated geometrically, whereas the calendering process and volume change due to intercalation in LIB are modeled physically by a discrete el- ement approach. A combination of a tracking algorithm and a resistor network approach is developed to predict the con- nectivity and effective conductivity for the various densified structures. For SOFC, a systematic study of the influence of morphology on connectivity and conductivity is performed on a large number of assemblies with different compositions and particle size ratios between 1 and 10. In comparison to percolation theory, an enlarged percolation area is found, es- pecially for large size ratios. It is shown that in contrast to former studies the percolation threshold correlates to varying coordination numbers. The effective conductivity shows not only an increase with volume fraction as expected but also with size ratio. For LIB, a general increase of conductivity during the intercalation process was observed in correlation with increasing contact forces. The positive influence of cal- endering on the percolation threshold and the effective conductivity of carbon black is shown. The anisotropy caused by the calendering process does not influence the carbon black phase.
基金supported by the National Natural Science Foundation of China(No.51973023)Sichuan Science and Technology Program(No.2021JDRC0014).
文摘The"solid-liquid"behavior of vitrimers have not been systematically investigated.Herein,a series of"solid-liquid"vitrimers bearing varying contents of dynamic boronic ester bonds were synthesized via thiol-ene click reactions.These vitrimers allow for flexibile modulation of their network structures and thus show a range of intriguing properties including high stretchability,flexible transition from elasticity to plasticity,strong strain rate dependence,and solid-liquid performance.The dynamic association rate of boronic ester bonds within these vitrimers could be apparently accelerated via increasing the content of boronic ester,which could be used to shape-program the flat vitrimer films into various complex 3D structures just with external force.Materials with such versatile dynamic behavior may open up a range of new applications.
文摘Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) have been known for decades to mediate neuroendocrine and vasodilative actions via G-protein-coupled receptors of Class B. These are targets of imaging probes for positron emission tomography (PET) or single photon emission tomography (SPECT) in tumor diagnostics and tumor grading. However, they play only a subordinate role in the development of tracers for brain imaging. Difficulties in development of non-peptide ligands typical for cerebral receptors of PACAP and VIP are shared by all members of Class B receptor family. Essential landmarks have been confirmed for understanding of structural details of Class B receptor molecular signalling during the last five years. High relevance in the explanation of problems in ligand development for these receptors is admitted to the large N-terminal?ectodomain markedly different from Class A receptor binding sites and poorly suitable as orthosteric binding sites for the most small-molecule compounds. The present study is focused on the recently available receptor ligands for PAC1, VPAC1 and VPAC2 receptors as well as potential small-molecule lead structures suitable for use in PET or SPECT. Recently, biaryl, cyanothiophene and pentanamide structures with affinities in nM-range have been proposed as non-peptide ligands at VPAC1 and VPAC2 receptors. However, most of these ligands have been classified as non-competitive related to the orthosteric binding site of endogenous peptide ligands of VPAC receptors. For PAC1 receptors have been identified hydrazide compounds for which an inhibitory and potentially competitive mechanism of receptor binding has been postulated based on molecular docking studies.
文摘Neuropeptide receptors of the brain and spinal cord are parts of the pain circuits targeted by analgesic drugs. Some of these receptors have been found in the central nervous system as well as in intracranial vascular structures and achieved revival of attention because of their role in acute and chronic pain syndromes. A number of them are of high clinical relevance for e.g. migraine. Others participate in symptoms of rare diseases like amyotrophic lateral sclerosis. Here we will focus on five of the neuropeptide receptors and their non-peptide ligands potentially or already successfully used as PET probes. Opioid receptors and neurotensin receptors are known to mediate analgesic actions. Bradykinin and calcitonin gene-related peptide (CGRP) receptors are known to be involved in the regulation of vascular tone and inflammatory responses, and neurokinin receptors play a role in the occurrence of pain perception in a rather indirect manner. Most experiences as PET tracers have been gathered with opioid receptor ligands and neurokinin receptor ligands. The most innovative fields revealed by the studies summarized in this report are the ligands of κ opioid receptors and CGRP receptors for which a first PET tracer was presented recently.
基金supported by the National Natural Science Foundation of China(52170087,21777118)The INM authors thank Eduard Arzt(INM)for his continuing support.L.W.acknowledges funding from the China Scholarship Council(CSC)via award number 201906260277.
文摘Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way.However,Faradaic materials hold the drawbacks of slow desalination rate due to the intrinsic low ion diffusion kinetics and inferior stability arising from the volume expansion during ion intercalation,impeding the engineering application of capacitive deionization.Herein,a pseudocapacitive material with hollow architecture was prepared via template-etching method,namely,cuboid cobalt hydroxide,with fast desalination rate(3.3 mg(NaCl)·g^(-1)(h-Co(OH)_(2))·min^(-1) at 100 mA·g^(-1))and outstanding stability(90%capacity retention after 100 cycles).The hollow structure enables swift ion transport inside the material and keeps the electrode intact by alleviating the stress induced from volume expansion during the ion capture process,which is corroborated well by in situ electrochemical dilatometry and finite element simulation.Additionally,benefiting from the elimination of unreacted bulk material and vertical cobalt hydroxide nanosheets on the exterior surface,the synthesized material provides a high desalination capacity(117±6 mg(NaCl)·g^(-1)(h-Co(OH)_(2))at 30 mA·g^(-1)).This work provides a new strategy,constructing microscale hollow faradic configuration,to further boost the desalination performance of Faradaic materials.
